"Diallo has served as a navigator of the UNSA Carrier Retribution under Captain Alder for over a decade. As navigator, his primary responsibility is to be aware of ship position at all times. Additional responsibilities include planning the journey and advising the captain of estimated accuracy to destinations in drop transit."

Diallo was a soldier who served aboard the Retribution. Following the attack on Earth, he informs Nick Reyes, then a Lieutenant, that via the chain of succession, he is the new captain of the Retribution.

Diallo survived the initial crashing of the Retribution and continued to fight alongside with Reyes on Mars, however he was killed when he pushed Reyes out of the line of fire, getting himself shot multiple times by an SDF gunship.